This invention relates to coil winding equipment, and more particularly to a chuck for holding a winding form during winding, a method of utilizing this chuck, and a winding form for carrying out the method.
The winding of small winding forms intended to be used as components of electronic circuits poses numerous problems in that the wire used for winding these forms is extremely fine, and it is necessary to guide it correctly and always to know its position so that it can first be placed on the form to be wound, then wound around the core of this winding form, and picked up at the end of winding to be placed on the next form to be wound, by an automatic winding machine. The difficulty thereupon consists in being able to weld each end of the winding wire to a metal path of the winding form in view of the extremely small size of both the winding wire and the form, i.e., of the core on which it is wound and of the metal paths to which it must be attached.
One solution to this problem is proposed in co-pending U.S. Ser. No. 656,137, now U.S. Pat. No. 5,261,615, describing a method wherein the winding wire remains stretched between points of known positions from which it is always possible to recover it by a suitable means in order to shift it to a required location for welding there. It is nevertheless necessary, with this prior art method, to go after the winding wire in order to bring it into position ready to be welded.
It is an object of this invention to provide an improved chuck, as well as a method of using it and an associated winding form, by means of which this relatively delicate step of going after the wire can be avoided by directly positioning the ends of the wire so that they can at once be welded on suitable metal paths without having to be picked up.
To this end, in the form-holding chuck according to the present invention, the improvement comprises at least one pin for guiding the winding wire, and the jaws of the chuck are shaped in such a way as to give access to at least one metal portion of a head of the winding form.
In the method of operating the inventive chuck, a winding mechanism as a flyer places the winding wire on the first of the metal portions, being guided by the first of the guide pins, as well as by a front face of a chuck jaw adapted as a wire guide, and after winding has been carried out, the winding mechanism takes the winding wire away, passing above the second of the metal portions, being guided by the second of the guide pins.
The winding form for implementing the foregoing method comprises a winding core and at least one head having two metal portions. In the coil produced from the inventive winding form, the two ends of the winding wire are welded to the two metal portions of the head of the winding form.
Other objects and advantages of the invention, the make-up and operation of the chuck, the method of utilizing it, as well as the make-up of the winding form and the winding, will become apparent from the following detailed description of preferred embodiments of the invention, taken in conjunction with the accompanying drawings.